aba64100-c10b-4de3-e044-0003ba6f30bd English dataset Mary Mowat British Geological Survey (BGS) +44 (0)131 667 1000 +44 (0)131 668 4140 offshoredata@bgs.ac.uk pointOfContact 2011-08-30 MEDIN Discovery Metadata Standard Version 2.3.5 urn:ogc:def:crs:EPSG::4326 OGP 2001 Strategic Environmental Assessment SEA2 Technical report - Background information on marine mammals in the North Sea 2001-08-01 publication BGS_SEA_21 British Geological Survey This report is a contribution to the Department of Trade and Industry's (now Department of Energy and Climate Change) Strategic Environmental Assessment SEA2. Eight marine mammal species occur regularly over large parts the North Sea: harbour seal, grey seal, harbour porpoise, bottlenose dolphin, white-beaked dolphin, Atlantic white-sided dolphin, killer whale and minke whale. A further 15 cetacean species and five pinniped species are reported less frequently in the region. This report describes the distribution and abundance of these mammals and their ecological importance. The harbour porpoise is the most numerous marine mammal in the North Sea, with a population estimated at 268,000 in summer 1994. The northern and central SEA2 areas are particularly important areas for the harbour porpoise. Marine mammals make use of sound for a variety of purposes: finding prey, detecting predators, communication and probably navigation. The offshore oil and gas industry generates underwater noise at every stage of the process: during exploration seismic surveys, drilling, production and decommissioning. The effects of these different sources of underwater noise on marine mammals are discussed. The use of explosives for underwater cutting and demolition during the decommissioning of platforms and installations may pose a serious threat to some marine mammals. The effects of pollution on seals and cetaceans are discussed, including the effects of oil spills. Large whales can be killed by being struck by ships; increased shipping traffic in an area would increase this threat. Paul Henni British Geological Survey (BGS) +44 (0)131 667 1000 Murchison House, West Mains Road Edinburgh EH9 3LA UK offshoredata@bgs.ac.uk custodian Department for Energy and Climate Change (DECC) +44 0300 060 4000 +44 (0) 1823 284077 Admiralty Way London SW1A 2HD UK enquiries@decc.gsi.gov.uk originator notPlanned Documents NDGO0001 Cetacean behaviour Cetacean morphology and physiology Cetacean abundance Industrial activity Industrial discharges Seal behaviour Seal morphology and physiology Seal abundance SeaDataNet Parameter Discovery Vocabulary 2011-03-25 revision Species distribution GEMET - INSPIRE themes, version 1.0 2008-06-01 publication crust sediment SeaVoX Vertical Co-ordinate Coverages 2008-06-01 publication The SEAs data were produced as part of the UK Department of Energy and Climate Change's Offshore Energy Strategic Environmental Assessment programme; Crown Copyright, all rights reserved. The DECC SEA must be acknowledged in any maps or publications that make use of the data. All the data files are freely available to the public. The Strategic Environmental Assessment (SEA) data portal provides free access to available data and reports which have been produced through the SEA process. The site is run and managed by BGS on behalf of the Department of Energy and Climate Change (DECC). Many files can be downloaded directly from this website. Those that are too large to download can be ordered via the website for postal delivery from BGS. BGS (NERC) has been contracted by DECC to publish SEA datasets on its behalf. All intellectual property rights (including , without limitation, copyrights, database rights and all other rights which subsist or may at any time in the future subsist in the Dataset(s)) in the Dataset(s) ('Intellectual Property Rights') are owned by DECC (formerly the Department of Trade and Industry, and the Department for Business, Enterprise and Regulatory Reform). BGS has been authorised by DECC to use SEA datasets for all purposes but on a 'not-for-profit basis'. BGS has been authorised by DECC to pass on SEA datasets to third parties so that they can use them for all purposes but on a 'not-for-profit' basis. intellectualPropertyRights 5 English biota environment oceans utilitiesCommunication SeaVoX salt and fresh water body gazetteer 2006-01-01 revision North Sea -1.9 3.3 52.8 61.8 2001-01-01 2001-01-01 http://www.offshore-sea.org.uk/site/index.php http://www.bgs.ac.uk/data/sea/home.html Strategic Environmental Assessment (SEA) data portal The Strategic Environmental Assessment (SEA) data portal provides free access to available data and reports which have been produced through the UK Department of Energy and Climate Change SEA process. The site is run and managed by BGS on behalf of the Department of Energy and Climate Change (DECC). Many files can be downloaded directly from this website. Those that are too large to download can be ordered via the website for postal delivery from BGS. download dataset The report was prepared by scientists from the Sea Mammal Research Unit (SMRU) Gatty Marine Laboratory, University of St Andrews in August 2001 using a variety of sources as part of the UK Department of Energy and Climate Change's Offshore Energy Strategic Environmental Assessment programme. There is extensive information on the distribution and abundance of grey seals around Britain from annual aerial surveys of breeding colonies and from over 100 animals fitted with satellite-relayed data loggers. Information on harbour seals is available from aerial surveys and VHF telemetry. There is also extensive information on distribution in the North Sea from a number of summer sightings surveys (SCANS-94, NASS-89 and NILS-95). Estimates of abundance are available from these surveys for some species. There are also many records from year round surveys by the European Seabirds at Sea Consortium (ESAS) since 1979, from cetacean observations made during seismic surveys in 1996-98, and sightings by voluntary observers compiled by the Sea Watch Foundation.